Atomic force microscope employing beam tracking

摘要

A scanning probe microscope such as an atomic force microscope for measuring a feature of a sample surface with a sharp probe over an area of interest by means of a collimated light beam reflected from a reflective surface responsive to movement of the sharp probe relative to the sample surface, the movement detected by a position sensitive photodetector, includes a scanner having one end fixed and another end free and attached to the sharp probe for moving the sharp probe. Also fixed to the free end of the scanner is a mount for a beam tracking lens which is interposed into the collimated light beam to cause a focus spot of the light beam to track translational movement of the reflective surface caused by the scanner. In this way, a wide range of scanning ranges up to about 100x100 square micrometers is accommodated as is scanner head and scanner mode switching without the need to disturb the sample. Preferably the beam tracking lens is bi-convex and the source of the collimated light beam is a diode laser.